After 50 years, a program to reintroduce Eastern Quolls to Australian mainland has seen success with 15 offspring found in the pouches of females off the NSW south coast.

The furry carnivore, usually about the size of a domestic cat, disappeared from the mainland in the 1960s but remained in Tasmania.

Researchers for the program have hailed the discovery for showing huge potential for long-term success for the Eastern Quoll.